If you talk to Klaas Plas of Berry Konsult about coir substrates, you’ll hear the word ‘foolproof’ come up several times. But what does he mean? Klaas: ”It’s really quite difficult to mess up with coir products. They’re easy to humidify, so any fluctuations in humidity levels, for example due to a sudden change in the weather, can be corrected immediately. That, of course, is crucial in strawberry farming.” We spoke with Klaas about his consulting business and his experiences with coir as a growing medium.
The early days of coir products
From the Netherlands, Germany, Poland, Hungary and Romania to Slovakia, Ukraine, Australia and Canada; strawberry growers all over the world come to Berry Konsult’s Klaas Plas for advice on all things strawberry. During on-site visits or remote consultations, he offers advice on varieties, growing techniques, fertilisation, irrigation and (biological) crop protection. He was introduced to coir early on. Klaas: “I first came across coir back in 1996, when coir products were brand new. I didn’t fall in love right away, because there were quality issues, caused mainly by the high salt content. That shortcoming has now been addressed and I now love working with coir. In fact, I’ve been using it heavily since 2007.”
Peat versus coir
Klaas has seen the excellent results of coir substrates first-hand, such as with growers in Hungary. “Many growers there also grow their own plants, but they used to do so on peat, which is a very picky substrate when it comes to humidity levels. The result: A whopping failure rate up to 50%. I have been telling growers about coir since 2009, with Dutch Plantin supplying the bulk, and crop failure has almost disappeared entirely. Almost all Hungarian growers I visit now use coir substrates. For strawberries I recommend using cocopeat, rather than the coarser fibres.”
Lower chance of Phytophthora
Klaas has also noticed that using coir has helped growers in the Netherlands and Germany become less reliant on crop protection products. “One of my German clients grows old English varieties. The strawberries are delicious, but the plants are very susceptible to
Phytophthora. Having boarded the coir train, this customer is now achieving fantastic results. Due to the open structure of coir, the plants are not nearly as prone to Phytophthora, which means that many of my clients no longer need to use crop protection products to combat it. Others have switched to biological crop protection, such as lacewings or other predators, marking a positive development. I’m very grateful that I was able to play a part.”
Coir from Dutch Plantin
Why Dutch Plantin is one of the coco coir producers with whom Klaas Plas works? Dutch Plantin’s Wim Roosen: “Because we ship products straight from our factories in the Netherlands and India, guaranteeing consistent quality. Our cocopeat has had a high 25-30% air content for 25 years, without the need for added perlite, for instance. We have also launched Ozone, our new, unique blend for growers looking for a higher air content up to 40%.”
Costs rising worldwide
In the past two years, the costs of importing goods from Asia has skyrocketed. Wim Roosen: “Unfortunately, coir prices have risen considerably, but we hope that prices will drop in the long run.” It should be noted that other substrates, such as perlite and rock wool are also rising rapidly now that energy costs have spiked. Worldwide demand for substrates is growing, and we will need all the substrates we can get our hands on. You can’t go wrong with Dutch Plantin coir. Wim: “You need stable coir for consistent, long-term performance beyond just the first year.”
To find out more about Dutch Plantin products, check out our website.


